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arXiv · 1709.05353

The DEdicated MONitor of EXotransits and Transients (DEMONEXT): System Overview and Year One Results from a Low-Cost Robotic Telescope for Follow-Up of Exoplanetary Transits and Transients

Steven Villanueva Jr.·B. Scott Gaudi·Richard W. Pogge·Jason D. Eastman·Keivan G. Stassun·Mark Trueblood·Patricia Trueblood
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Abstract

We report on the design and first year of operations of the DEdicated MONitor of EXotransits and Transients (DEMONEXT). DEMONEXT is a 20 inch (0.5-m) robotic telescope using a PlaneWave CDK20 telescope on a Mathis instruments MI-750/1000 fork mount. DEMONEXT is equipped with a $2048\times2048$ pixel Finger Lakes Instruments (FLI) detector, a 10-position filter wheel with an electronic focuser and $B$, $V$, $R$, $I$, $g'$, $r'$, $i'$, $z'$, and clear filters. DEMONEXT operates in a continuous observing mode and achieves 2-4 mmag raw, unbinned, precision on bright $V<13$ targets with 20-120 second exposures, and 1 mmag precision achieved by binning on 5-6 minute timescales. DEMONEXT maintains sub-pixel ($<0.5$ pixels) target position stability on the CCD over 8 hours in good observing conditions, with degraded performance in poor weather ($<1$ pixel). DEMONEXT achieves 1-10% photometry on single-epoch targets with $V<17$ in 5 minute exposures, with detection thresholds of $V\approx21$. The DEMONEXT automated software has produced 143 planetary candidate transit light curves for the KELT collaboration, and 48 supernovae and transient light curves for the ASAS-SN supernovae group in the first year of operation. DEMONEXT has also observed for a number of ancillary science projects including Galactic microlensing, active galactic nuclei, stellar variability, and stellar rotation.

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Steven Villanueva Jr., B. Scott Gaudi, Richard W. Pogge, Jason D. Eastman, Keivan G. Stassun, Mark Trueblood, Patricia Trueblood. 2017-09-15. The DEdicated MONitor of EXotransits and Transients (DEMONEXT): System Overview and Year One Results from a Low-Cost Robotic Telescope for Follow-Up of Exoplanetary Transits and Transients. https://doi.org/10.1088/1538-3873%2Faa9603

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